Recently, X-ray diagnosis has advanced mainly in the field of circulatory organs with improvements in catheter techniques. For example, an X-ray diagnostic apparatus for diagnosis of circulatory organs is formed from an X-ray generation unit, an X-ray detection unit, a holding device which holds them, a bed, a top, a signal processing unit, a display unit, and the like. The holding device allows X-ray imaging at an optimum position from an optimum direction by causing a C-arm or Ω-arm to pivot, rotate, or move about an object.
CT-like imaging (to be referred to as CTL hereinafter) is performed using an X-ray diagnostic apparatus. CTL is often used since CT imaging can be readily performed during an angiography procedure. More specifically, CTL is a technique of generating a tomographic image like a CT image by reconstructing volume data based on projection data collected while rotating the C-arm. CTL is used for confirmation of blood vessel running in an arteriovenous malformation, determination of plaque characteristics, hepatic arteriography in transcatheter arterial embolization for hepatocellular carcinoma, arterial portography, puncture guidance for, for example, percutaneous radiofrequency ablation as the treatment for malignant tumor in a liver, needle biopsy of each organ such as a lung, kidney, liver, or bone marrow, and the like.
In CTL, however, there is a problem that the C-arm cannot be continuously rotated in one direction, unlike CT. FIG. 14 is a schematic view for explaining torsion of cooling pipes when an arm is rotated according to a conventional example. The cooling pipes include a low-temperature pipe D1 and a high-temperature pipe D2. The low-temperature pipe D1 is a channel for a refrigerant. The high-temperature pipe D2 is a channel for the refrigerant warmed by an X-ray tube. In addition, a cooling device is a power source for circulating the refrigerant within an X-ray tube holding device through the cooling pipes. The cooling device is included in, for example, a column supporting the arm. When the arm is rotated by 360°, the high-temperature pipe D2 is twisted and entangled around the low-temperature pipe D1 by 360°, as shown in FIG. 15. That is, when the arm is continuously rotated in one direction, the low-temperature pipe D1 and the high-temperature pipe D2 are twisted and entangled around each other many times, and eventually break.
The cooling device is not mounted on the C-arm, thereby causing torsion of the cooling pipes. Similarly, a high-voltage generation device for applying a voltage to the X-ray tube is not mounted on the C-arm, thereby causing torsion of a high-voltage line for transferring a high voltage. Since the cooling device and the high-voltage generation device are large in size and heavy, if they are mounted on the C-arm, the C-arm unwantedly becomes large in size. In consideration of arrangement of another medical device near a blood vessel imaging device or an operator who stands near by the blood vessel imaging device to perform a procedure, the C-arm needs to be small in size. Therefore, it is difficult to mount the cooling device and the high-voltage generation device on the C-arm.